<p>在这种情况下,b1和b2都有相同的a</p>
<pre><code>class A:
def __init__(self):
self.var=1
class B:
a=A()
def __init__(self):
pass
b1=B()
b2=B()
b1.a.var=2 #changing "var" in b1 would also change it in b2
print(b2.a.var) # prints 2
</code></pre>
<p>我应该怎么做才能在B中有两个不同的A实例?你知道吗</p>